What is the status of a 4.4 cm abdominal aortic aneurysm (AAA) with mural thrombus after endovascular repair?

From the Guidelines

The patient with a 4.4 cm abdominal aortic aneurysm (AAA) and mural thrombus after endovascular repair should undergo baseline surveillance imaging with CT, and if no evidence of endoleak or sac enlargement is found, continued surveillance with duplex ultrasound at 12 months and then annually thereafter is recommended. According to the 2022 ACC/AHA guideline for the diagnosis and management of aortic disease 1, the role of routine surveillance after endovascular aneurysm repair (EVAR) is to identify endoleak, sac growth, endograft migration, or endograft failure.

Key Considerations

• The presence of mural thrombus after EVAR is not uncommon and typically doesn't require additional intervention unless there are signs of endoleak, aneurysm expansion, or symptoms 1.
• CT is the gold standard for follow-up imaging after EVAR, but duplex ultrasound can be used for surveillance if no concerning findings are observed on the initial CT scans 1.
• The patient should be monitored for any new symptoms like abdominal or back pain, or signs of distal embolization, which should prompt immediate medical attention.

Surveillance Imaging

• Baseline surveillance imaging with CT is recommended after EVAR 1.
• If no evidence of endoleak or sac enlargement is found, continued surveillance with duplex ultrasound at 12 months and then annually thereafter is recommended 1.
• Additional cross-sectional imaging with CT or MRI of the abdomen and pelvis every 5 years postoperatively may be reasonable in patients with AAA treated with EVAR 1.

Management

• Blood pressure control is essential, targeting less than 130/80 mmHg with medications like ACE inhibitors or ARBs.
• Statin therapy should be maintained regardless of cholesterol levels for its pleiotropic effects on vascular health.
• Smoking cessation is critical if the patient smokes.
• The patient should continue taking antiplatelet therapy such as aspirin 81 mg daily indefinitely, unless contraindicated.

From the Research

Status of a 4.4 cm Abdominal Aortic Aneurysm (AAA) with Mural Thrombus after Endovascular Repair

• The status of a 4.4 cm abdominal aortic aneurysm (AAA) with mural thrombus after endovascular repair is a complex issue, with various factors influencing the outcome 2, 3, 4, 5, 6.
• Endovascular repair is a commonly used treatment modality for AAA, with several studies demonstrating its effectiveness in preventing rupture and reducing mortality 4, 6.
• However, the presence of mural thrombus within the endograft's main body has been associated with an increased risk of thromboembolic events, although the study by 2 found no significant association between mural thrombus accumulation and the occurrence of thromboembolic events over time.
• The study by 5 found that age, intraluminal thrombus volume, and type II endoleak were significant predictors of sac enlargement after endovascular repair, highlighting the importance of careful patient selection and monitoring.
• Compliance with post-EVAR imaging surveillance is crucial for detecting potential complications, such as sac enlargement or endoleak, and ensuring long-term success of the procedure 6.
• Factors such as smoking, excess alcohol consumption, and cardiac risk factors have been associated with poor follow-up after EVAR, emphasizing the need for close monitoring and patient education 6.

Predictors of Sac Enlargement after Endovascular Repair

• Age, intraluminal thrombus volume, and type II endoleak have been identified as significant predictors of sac enlargement after endovascular repair 5.
• The study by 3 highlighted the importance of recognizing and treating endoleaks, as they can lead to persistent pressurization of the aneurysm sac and growth.
• The presence of mural thrombus within the endograft's main body has been associated with an increased risk of thromboembolic events, although its impact on sac enlargement is still unclear 2.

Importance of Follow-up Imaging Surveillance

• Regular follow-up imaging surveillance is essential for detecting potential complications, such as sac enlargement or endoleak, and ensuring long-term success of the procedure 4, 6.
• Compliance with post-EVAR imaging surveillance is crucial, with factors such as smoking, excess alcohol consumption, and cardiac risk factors associated with poor follow-up 6.
• The study by 6 found that patients undergoing elective open AAA repair in the VA hospital system had lower long-term mortality compared with patients who underwent endovascular repair, highlighting the need for careful patient selection and monitoring.